Tuning the surface electronic structure of a Pt3Ti(111) electro catalyst. Issue 29 (11th February 2016) - Paßens, M.
Abstract : Combining voltage dependent STM imaging with ab initio DFT calculations to identify the exact termination of an electro catalyst. Abstract : Increasing the efficiency and stability of bimetallic electro catalysts is particularly important for future clean energy technologies. However, the relationship between the surface termination of these alloys and their catalytic activity is poorly understood. Therefore, we report on fundamental UHV-SPM, LEED, and DFT calculations of the Pt3 Ti(111) single crystal surface. Using voltage dependent imaging the surface termination of Pt3 Ti(111) was studied with atomic resolution. Combining these images with simulated STM maps based on ab initio DFT calculations allowed us to identify the three upper layers of the Pt3 Ti(111) single crystal and their influence upon the surface electronic structure. Our results show that small changes in the composition of the second and third atomic layer are of significant influence upon the surface electronic structure of the Pt3 Ti electro catalyst. Furthermore, we provide relevant insights into the dependence of the surface termination on the preparation conditions.